Point Features

These are features or geographically-defined occurences whose location can be represented by a single x, y or x, y, z location. Points have no linear or area dimensions but simply define the location of a physical feature ( e.g. water quality sites, NPDES points, survey points, utility poles UIC points) or an event (spill sites, accidents, crime).

Line Features

Lines represent features that have a linear extent in the GIS database but no area dimensions. Streams, roads, water mains, etc.

Area Features

Area features, alo called "polygons", have a defined two-dimensional extent and are delimited by boundary lines that encompass the area. Some examples of area features are: ponds, lakes, watersheds, soil types, geology types, various boundaries, etc.